Two Methods of Cleaning the Excess Stone (Full Arch)
Knife Method
Spatula Method
Stone setting
(Hardness)
Hard setting stage
(Stone is becoming set
and is difficult to simply wipe away)
Soft setting stage
(Stone is soft enough for
easy manipulation & wet cleaning)
5
10
Setting time in minutes
(working time)
Knife method
Stone pouring
Spatula method
Choose whichever method works best for you...
Technique
A. Knife
Method
Soft cutting/scraping
of the stone
B. Spatula
Method
Wipe the spatula
against the tray
Benefits
Ideal for multiple pours
(Over 5 cases at a time)
Good method for small quantity pours
(Usually 1 - 5 cases at a time)
Soft cleaning of the stone
while the stone is easy to manipulate
Tips
Cleaning with the knife involves cutting or scraping of the stone
while it is slightly set but is still somewhat soft. Depending on the
setting time, you usually have up to 15 minutes to clean the model
after pouring. Simply scrape the buccal and lingual (if not using the
insert) sides of the model as shown in the pictures above.
Depending on the setting time of your stone, wait 2-4 minutes
before cleaning so that the stone is soft enough to manipulate
yet set enough not to affect the integrity of the impression’s
sitting position.
If the stone has not set long enough and is too runny, cleaning
the excess stone may cause the impression to sink slightly on the
stone or be tilted to one side.
Two Methods of Cleaning the Excess Stone (Quadrant)
1. Cleaning with knife
Opposing side
Working side
Technique
Cleaning with the knife involves cutting or scraping of the stone
while it is slightly set but is still somewhat soft. Depending on the
setting time, you usually have up to 15 minutes to clean the model
after pouring. Simply scrape the buccal and lingual sides of the
model as shown in the pictures above.
Benefits
Ideal when pouring multiple cases (over 10 cases at a time). The knife can
be used to scrape away the stone up to approximately 15 minutes after
pouring. This gives the technician more time to pour models before the
stone is too set to go back and clean. Also, since the stone is somewhat
set, the impression cannot be unintentionally moved while cleaning.
2. Cleaning with spatula
Opposing side
Working side
Technique
Depending on the setting time of your stone, wait 2-4 minutes before cleaning
so that the stone is soft enough to manipulate yet set enough not to affect the
integrity of the impression’s sitting position. If the stone has not set long
enough and is too runny, cleaning the excess stone may cause the impression to
sink slightly on the stone or be tilted to one side.
Benefits
Usually works best when pouring a small number of cases
(less than 10 cases at a time). The spatula is used to clean
the stone while it is soft and easy to manipulate. The stone
is simply wiped from the tray.